I never want to evict pages to swap. If I loaded something, it's because I intend to run it, and I never want to wait. If there's not enough RAM, I'd rather have a userspace OOM killer kill the process early so I know I'm trying something impossible. (Or rely on the kernel OOM killing if it's actually capable of doing its job, but last I tried the default behavior under heavy memory pressure was to free any pages that can be restored from disk, even if swap is disabled, which makes the system equally unusable.) I don't care if rarely used pages are "wasted" by being kept in RAM. I want good worst-case performance, not good average-case performance.